The Foreign Office is warning that air strikes on Isis forces, as in the Syrian border town of Kobani, may mean that Britons travelling around the world will be targeted. Photograph: Anadolu Agency/Getty Images

Britons travelling abroad are being warned that they could be targeted by extremists seeking revenge for UK air strikes against Islamic State (Isis).

The Foreign Office (FCO) has updated its travel advice for all destinations across the globe that British nationals faced a heightened threat of attack from “groups or individuals motivated by the conflict in Iraq and Syria”.

It urges all Britons living or travelling overseas to be vigilant at the current time.

The FCO said that it was responding to the “generalised threat” rather than warnings of a specific attack.

The move comes after home secretary Theresa May announced in August that the UK national terror threat level had been raised from substantial to severe, meaning an attack is considered highly likely.

Last month, parliament gave the go-ahead for the RAF to carry out air strikes against Isis forces in Iraq and the government has been supplying arms to the Kurdish peshmerga militias fighting the extremists.

The updated FCO advice states: “There is considered to be a heightened threat of terrorist attack globally against UK interests and British nationals from groups or individuals motivated by the conflict in Iraq and Syria. You should be vigilant at this time.”

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